The black currant shrub is native to Europe and parts of Asia and is particularly popular in Eastern Europe and Russia. Traditional herbalists uphold that black currant has diuretic (increases urine flow), diaphoretic (promotes sweating), and antipyretic (fever reducer) properties. In Europe, it has been used topically (applied to the skin) to treat skin disorders, such as atopic dermatitis, and as part of gargles to treat sore throats. Black currant juice has been boiled down into a sugary extract, called Rob, to treat sore throat inflammation, colds, the flu, and febrile (fever) illness. A mixture made from black currant bark has been used to treat calculus (hardened plaque), edema (swelling), and hemorrhoids.

With a vitamin C content estimated to be five times that of oranges (2,000 milligrams/kilogram), black currant has potential dietary benefits. Black currant is also rich in rutin and other flavonoids, which are known antioxidants. Because of black currant's high essential fatty acid content, researchers believe that it may be effective in the treatment of inflammatory conditions and pain management, as well as in regulating the circulatory system and increasing immunity.

As a medicinal treatment, black currant seed oil is the most commonly used part of the plant and is available in capsule form. The effectiveness of black currant seed oil is mixed and safety concerns seem to be minor in non-allergic people.

These uses have been tested in humans or animals. Safety and effectiveness have not always been proven. Some of these conditions are potentially serious, and should be evaluated by a qualified healthcare provider.

GRADE *

There is currently a lack of information in humans on the effectiveness of black currant juice as an antioxidant.

C

Chronic venous insufficiency is a condition in which damaged valves in the veins or a blood clot in the leg may cause ongoing swelling or blood pooling in the legs. Black currant treatment may benefit women with blood flow disorders, such as chronic venous insufficiency. More study is needed in this area.

There is currently a lack of information in humans on the effectiveness of black currant seed oil in changing immune system function.

C

Results are conflicting and more study is warranted to determine whether black currant is effective for muscle stiffness.

C

Certain components in black currant called anthocyanosides may be helpful for improving night vision. However, additional studies are needed.

C

There is currently a lack of information in humans on the effectiveness of black currant seed oil for nutrition supplementation in phenylketonuric patients.

C

Early study shows promise for the use of black currant seed oil in reducing the signs and symptoms of rheumatoid arthritis. However, additional study is needed to confirm these findings.

C

There is currently a lack of information in humans on the effectiveness of black currant seed oil for stress. More research is needed in this area.

C

* Key to grades

A: Strong scientific evidence for this useB: Good scientific evidence for this useC: Unclear scientific evidence for this useD: Fair scientific evidence for this use (it may not work)F: Strong scientific evidence against this use (it likley does not work)

Tradition / Theory
The below uses are based on tradition, scientific theories, or limited research. They often have not been thoroughly tested in humans, and safety and effectiveness have not always been proven. Some of these conditions are potentially serious, and should be evaluated by a qualified healthcare provider. There may be other proposed uses that are not listed below.

As a dietary supplement, black currant is available in 500 milligram and 1,000 milligram capsules that typically contain black currant seed oil, vegetable glycerine, and gelatin. Black currant is likely safe when used at a maximum dose of 1,000 milligrams (500-1,000 milligrams are often used per day). Black currant juice is also commercially available and has been taken in doses up to 1.5 liters per day, when mixed with apple juice. Maximum doses of black currant seed oil used in clinical trials range from 4.5-6 grams per day up to eight weeks, although there is no proven effective dose, and safety has not been established. Black currant anthocyanins have been taken in doses of 7.7-50 milligrams for up to two months. Based on some herbal textbooks, there is a lack of reported toxicity concerns with black currant consumed as food or ingested in 500 milligram tablets three times a day.

Children (under 18 years old)

There is no proven safe or effective dose for black currant in children.

Safety
The U.S. Food and Drug Administration does not strictly regulate herbs and supplements. There is no guarantee of strength, purity or safety of products, and effects may vary. You should always read product labels. If you have a medical condition, or are taking other drugs, herbs, or supplements, you should speak with a qualified healthcare provider before starting a new therapy. Consult a healthcare provider immediately if you experience side effects.

Allergies

Avoid in individuals with a known allergy or hypersensitivity to black currant, its constituents, or plants in the Saxifragaceae family.

Side Effects and Warnings

In general, there is a lack of safety information about black currant. Anecdotal information indicates that black currant seed oil may cause diarrhea. Furthermore, some people are not able to tolerate black currant seed oil in capsule form, resulting in diarrhea and other mild gastrointestinal symptoms. The gamma-linolenic acid in black currant may alter blood pressure. Use cautiously in patients with high blood pressure or those taking blood pressure medication.

Avoid in patients with hemophilia or those on anticoagulants (blood thinners) unless otherwise recommended by a qualified healthcare provider, as black currant may enhance the effects of anticoagulants.

Use cautiously in pregnant and breastfeeding women, and in children and the elderly, as their immunity and bodily functions are compromised or underdeveloped.

Use cautiously in those with venous disorders, as black currant may increase peripheral blood flow and circulation.

Pregnancy and Breastfeeding

Black currant is not recommended in pregnant or breastfeeding women due to a lack of available scientific evidence; therefore, pregnant women and breastfeeding mothers should avoid the use the black currant seed oil, unless a qualified healthcare provider recommends otherwise.

Black currant seed oil may have antibacterial activity; use cautiously with antibiotics and anti-ulcer medications.

Black currant may increase the risk of bleeding when taken with drugs that increase the risk of bleeding, such as warfarin (Coumadin®), clopidogrel (Plavix®), aspirin (Bayer®, Ecotrin®, St John®), enoxaparin (Lovenox®), and dalteparin (Fragmin®).

Black currant may increase the risk of bleeding when taken with herbs and supplements that are believed to increase the risk of bleeding. Multiple cases of bleeding have been reported with the use of Ginkgo biloba, and fewer cases with garlic and saw palmetto.

Black currant may have monoamine oxidase inhibitor (MAOI) effects. Use cautiously with herbs and supplements with antidepressant activity.

Black currant may interact with anti-inflammatory herbs and supplements; use cautiously due to possible additive effects.

Black currant anthocyanins have antioxidant effects and caution is advised when taking black currant with other agents with antioxidant effects.

Black currant may interact with anti-viral agents. Consult a qualified healthcare professional, including a pharmacist, to check for interactions.

Blackcurrant seed oil (BSO), a rich source of gamma-linolenic acid, may alter blood pressure. Use cautiously in herbs and supplements that may also alter blood pressure, due to possible additive effects.

Black currant seed oil may have immune-enhancing effects in the elderly, and should be used cautiously with other agents that affect the immune system.

Black currant fruit and juice contain rutin and other flavonoids. The flavonoids found in black currant belong to one of two classes: the anthocyanin class or the proanthocyanidin class. Caution is advised when taking black currant with other herbs or supplements containing these flavonoids due to additive effects.

Black currant fruit has a high vitamin C content. Use cautiously with other vitamin C supplements or multivitamin preparations.

The information in this monograph is intended for informational purposes only, and is meant to help users better understand health concerns. Information is based on review of scientific research data, historical practice patterns, and clinical experience. This information should not be interpreted as specific medical advice. Users should consult with a qualified healthcare provider for specific questions regarding therapies, diagnosis and/or health conditions, prior to making therapeutic decisions.